Dynamics of identified particles production in oxygen-oxygen collisions at \sqrt{s_{\mathrm{NN}} = 7 TeV using EPOS4

Abstract

The Large Hadron Collider (LHC) aims to inject oxygen (${}^{16}O$) ions in the next run into its experiments. This include the anticipated one-day physics run focusing on $OO$ collisions at center-of-mass energy \sqrt{s_{\mathrm{NN}} = 7 Tev. In this study, we have used recently developed version of the EPOS (EPOS4) to study the production of identified particles ($\pi^\pm$, $K^\pm$ and $p(\overline{p})$) in $OO$ collisions at 7 Tev. Predictions of transverse momentum ($p_T$) spectra, $\langle p_T \rangle$, integrated yield (dN/dy) for different centrality classes are studied. To provide insight into the collective nature of the produced particles, we look into the $p_T$-differential particle ratios ($K/\pi$ and $p/\pi$) and $p_T$-integrated particle ratios to ($\pi^++\pi^-$) as a function of charge particle multiplicity. The shape of the charge particle multiplicity ($dN/d\eta$) and $\langle p_T \rangle$ is well described by the EPOS4. The EPOS4 predictions for the ratios of $K/\pi$ and $p/\pi$ exhibit a systematic overestimation compared to the observed trends as a function of charged-particle multiplicity. Interestingly, the $OO$ results of $p_T$-integrated particle ratios shows a clear final state multiplicity overlap with $pp$, $p-Pb$ and $Pb-Pb$ collisions. EPOS4 mimics signs of collectivity and is one of the suitable candidates to study ultra-relativistic heavy-ion collisions. Furthermore, the foreseen data from $OO$ collisions at the LHC, when available, will help to better understand the heavy-ion-like behavior in small systems as well as help to put possible constraints on the model parameters.